Swiercz, who has been with the department for about 24 years, was placed on paid leave Saturday, Chicago Ridge Mayor Gene Siegel said. Swiercz started in the department as a firefighter, earning the rank of deputy chief about five years ago, the mayor said.

"I am surprised and shocked and do extend our best wishes to the victim," Siegel said. "That was an awful thing that she had to endure.

"There was never anything in his history that would make you think something like this would happen," he added. "I don't think there was any indication that something was wrong … It's really weird and hard to believe that this happened. That he could have done something like this."

Swiercz allegedly broke into the home of a woman in his condo building early Saturday while wearing a ski mask and carrying a folding knife. He also had duct tape, rope, a sex toy and lubricant, Assistant State's Attorney Dan Calandriello said in court.

Prosecutors alleged during a bond hearing that Swiercz put his hand on the woman's mouth while she was sleeping, then put a 3-inch blade to her throat and threatened to slash it. He held her hands together and forced her into the kitchen, where he pushed her against a cabinet, Calandriello said.

He threw her to the ground, grabbed her by the hair and slammed her to the ground multiple times, authorities allege. She suffered a swollen lip and a knot to the back on her head, Calandriello said.

Swiercz fled through the rear door of the home, and witnesses saw him throwing items into a Dumpster, Calandriello said.

Swiercz's attorney, Colleen McSweeney Moore, called the incident "out of character" for the deputy fire chief. She speculated in court that a medication error could have played a role in the incident, but in an interview outside court she could not elaborate.

Swiercz served as the fire chief in Worth between 2005 and 2008, his attorney said.

Police were called to the condo building about 2:35 a.m. Saturday on a report of a home invasion, the Tinley Park police said. Upon arriving at the scene, police said they found Swiercz in the condominium parking lot and took him into custody. The woman was treated for minor injuries at the scene, police said.